Contrast: Module for Estimating the Contrast of Biomolecular Assemblies (v1.1.1 - 2017)

Project: KinA:SDA 2:2 complex in 200mM NaCl, 50mM Tris, 150mM imidazole

Analysis of the dependence of I(0) upon fD2O

Approximate X-intercept = 0.504 (Determined from 2nd order polynomial fit to I(0)/c vs. fD2O)

Linear fit to √I(0)/c vs. fD2O (sign of √I(0)/c for fD2O > approximate X-intercept adjusted)

I(0) analysis
ParameterValueESD
χ261.59-
Slope-0.4280.003
Y-intercept0.2160.002
X-intercept0.5050.003

Contrast calculation parameters

In addition to water the solvent contains 3 other substance(s)

  1. Molecule(NaCl), Conc. = 0.200 mol/L, Volume of each formula unit to be calculated
  2. Molecule(H11.0C4.0NO3.0), Conc. = 0.050 mol/L, Volume of each formula unit to be calculated
  3. Molecule(H4.0C3.0N2.0), Conc. = 0.150 mol/L, Volume of each formula unit to be calculated

Subunit (1) - possesses 1 component(s), with a deuteration level of 0% and 95% of the total exchangeable protons accessible by the solvent

  1. Protein(228 residues - H1823.0C1135.0N297.0O343.0S7.0), 2 formula unit(s), Volume of each formula unit to be calculated

Subunit (2) - possesses 1 components(s), with a deuteration level of 85% and 100% of the total exchangeable protons accessible by the solvent

  1. Protein(48 residues - H401.0C244.0N68.0O77.0S2.0), 2 formula unit(s), Volume of each formula unit to be calculated


Contrast calculation results

Solvent and particle information in H2O
Volume
3)
ΣbX
(10-13cm)
ΣbN
(10-13cm)
ρX
(1010cm-2)
ρN
(1010cm-2)
Mass
(kDa)
Solvent
54.5930.028.18-1.689.403-0.5600.018
0.2029.378.9013.2126.9384.5090.058
0.05152.3185.9812.2012.2120.8010.121
0.1574.9101.4523.6913.5443.1630.068
Total-1578.48-84.849.506-0.511-
Subunit (1) - Number of hydrogen atoms = 3646.0, Number of exchangeable hydrogen atoms = 762.0
2.0062695.176467.6311027.2912.1971.75950.685
Total62695.176467.6311027.2912.1971.75950.685
Subunit (2) - Number of hydrogen atoms = 802.0, Number of exchangeable hydrogen atoms = 190.0
2.0013711.716845.657837.3012.2865.71611.690
Total13711.716845.657837.3012.2865.71611.690

The neutron scattering length density (1010cm-2) at any D2O fraction is:

The neutron contrast (1010cm-2) at any D2O fraction is:


Tabulated scattering length densities and contrasts
ρ (1010cm-2)Δρ (1010cm-2)
12Solvent12Total
X-RAY12.19712.2869.5062.6912.7802.707
NEUTRON
0.01.7595.716-0.5112.2706.2272.980
0.11.8795.8600.1741.7065.6862.420
0.21.9996.0040.8581.1415.1461.860
0.32.1206.1491.5430.5774.6061.300
0.42.2406.2932.2270.0134.0660.740
0.52.3606.4372.912-0.5523.5250.180
0.62.4806.5813.596-1.1162.985-0.380
0.72.6006.7264.281-1.6802.445-0.940
0.82.7216.8704.965-2.2451.905-1.500
0.92.8417.0145.650-2.8091.364-2.060
1.02.9617.1596.334-3.3730.824-2.620
Calculated match-point (fD2O)0.4021.1530.532
Experimental match-point (fD2O)--0.505(3)


Other related quantities

The density (in g.cm-3 @ 20°C) of the solvent at any D2O fraction is:

The molecular mass (kDa) at any D2O fraction is:

The partial specific volume (cm3g-1, fully proteated) is:

The X-ray scattering length per unit mass (1010cm.g-1) is: